Many types of optical discs include a data side and a label side. The data side is where the data is written to, whereas the label side allows the user to label the optical disc. Unfortunately, labeling can be an unprofessional, laborious, and/or expensive process. Markers can be used to write on optical discs, but the results are often decidedly unprofessional looking. Special pre-cut labels that can be printed on with inkjet or other types of printers can also be used, but this is a laborious process: the labels must be carefully aligned on the discs, and so on. Special-purpose printers that print ink or another marking material directly on the discs may be used, but such printers are relatively expensive. In the patent application entitled “Integrated CD/DVD Recording and Label”, filed on Oct. 11, 2001, and assigned Ser. No. 09/976,877, a solution to these difficulties is described, in which a laser is used to label optical discs.
Some user data-recordable optical discs are multi-session optical discs. Multi-session optically writable optical discs are those in which users can write data to the optical discs over multiple sessions. For example, a user may store a number of files on an optical disc on a Monday, and then on the following Wednesday store a number of additional files on the optical disc. Each time the user stores files on the optical disc is referred to as a session. Optically labeling optical discs that have multiple sessions on their data sides can be difficult, however. Even if blank space on the label side of an optical disc remains for future sessions, the optical disc drive may have difficulty determining which part of the label side is available for writing additional label information, and which part of the label side has already been written.